一种电流合成的PMSM转子初始位置检测方法

Method to detect the initial rotor position of PMSM based on current synthesis

转子初始位置检测是确保永磁同步电机能够成功启动的重要技术。启动时,必须准确获得静止状态下的转子初始位置,否则可能会导致反转、电流过大,甚至无法启动等问题。无传感器检测方法具有成本低廉等优点,受到广泛重视与研究。由于磁性材料存在磁通饱和现象,不同位置的转子主磁通将影响定子绕组的磁通饱和度,导致定子电感发生变化,电流也随之受影响。通过将方向互反的基本空间电压矢量注入到PMSM定子绕组中,激励出包含转子位置信息的三相定子电流,检测相电流峰值并进行电流合成,证明了此合成电流随转子位置呈三相正弦规律变化,并由此观测到静止状态下的转子初始位置,其与实际位置误差较小。该方法算法简洁,计算量小,具有较高的应用价值。

The detection of initial rotor position is an important technology to ensure the successful launch of permanent magret synchronous motor(PMSM).When starting,it is necessary to accurately obtain the initial position of the rotor in the static state,otherwise it may lead to problems such as reverse rotation,excessive current,and even failure to start.The method of sensorless detection has the advantage of low cost,so it has been widely studied.Due to the magnetic flux saturation of the magnetic material,main flux of rotor at different positions affected the flux saturation of stator winding,resulting in the change of stator inductance and current.By injecting the basic space voltage vector with reciprocal directions into the PMSM stator winding,it stimulated the three-phase currents containing rotor position information.After detecting the peak currents,current synthesis was conducted.It proves that the synthetic results conform to three-phase sine law with the change of rotor positions,and the initial rotor positions under static state are observed.The errors between observed positions and actual positions are small.The algorithm is easy to calculate and has great value in application.